Industrial truck having a pallet gripper

Abstract

The present invention relates to an industrial truck ( 10 ) having a load-receiving device ( 14 ) for the purpose of receiving a load ( 34 ), said load-receiving device ( 14 ) having a clamping device ( 23 ) in order to hold a clamping region ( 36 ) of the received load ( 34 ) in clamping engagement, the clamping device ( 23 ) having at least one clamping mechanism ( 24, 28 ) which can move between a clamping position and a release position, a drive arrangement ( 40 ), which is coupled to at least one of the clamping mechanisms ( 24, 28 ), for the purpose of moving the clamping mechanisms ( 24, 28 ) and an elastic device ( 42 ) which prestresses the clamping mechanisms ( 24, 28 ) towards one of the positions. With the industrial truck according to the invention, provision is made for the elastic device ( 42 ) to prestress the clamping mechanisms ( 24, 28 ) in the direction of the clamping position and to exert a clamping force on the clamping region ( 36 ) of the load ( 34 ) in the clamping position.

The invention claimed is: 
     
       1. Industrial truck having a load-receiving device for the purpose of receiving a load and lifting and dropping the load, said load-receiving device having a clamping device to hold a clamping region of the received load in clamping engagement, the clamping device being vertically moveable, and having at least one clamping means which is adapted to move between a clamping position and a release position, a drive arrangement, which is coupled to at least one of the clamping means by a coupling, for the purpose of moving the at least one clamping means and an elastic device which prestresses the at least one clamping means in a movement direction, wherein the elastic device prestresses the at least one clamping means in a direction of a clamping position for the purpose of exerting a clamping force on the clamping region of the load by means of the clamping means, the clamping means being in the form of lever elements which can be pivoted about a common pivot bolt towards and away from one another, and wherein the elastic device is connected with the lever elements respectively. 
     
     
       2. Industrial truck according to  claim 1 , wherein the clamping device is configured to exert the clamping force in the clamping position on the clamping region of the load for the purpose of holding the load, wherein the clamping force is applied essentially exclusively by the elastic device. 
     
     
       3. Industrial truck according to  claim 1 , wherein the clamping device is adjustable such that it is possible to set a distance between a plurality of clamping sections given a predetermined position of the drive arrangement, the clamping sections being portions of the clamping means configured to bear against the clamping region of the load. 
     
     
       4. Industrial truck according to  claim 3 , wherein at least one of the clamping means is of multi-part design, and a clamping jaw part, which bears at least one of the clamping sections, can be mounted on a support part of the clamping means in different mounting positions or at different mounting locations. 
     
     
       5. Industrial truck according to  claim 4 , wherein the clamping jaw part is attached to the support part such that it can be moved, on one of the clamping sections which is operatively connected to a second clamping means towards and away from said second clamping means, it being possible for the clamping jaw part and the support part to be fixed in relation to one another by means of a locking device. 
     
     
       6. Industrial truck according to  claim 1 , wherein the coupling between the at least one clamping means and the drive arrangement comprises a slot coupling, in which a pin, which is connected to a first part of the clamping means or the drive arrangement, is received in a slot in a coupling part, which is connected to a second part of the drive arrangement or clamping means such that it can be displaced in relation to said coupling part, the coupling being designed such that a force is transmitted between the pin and the coupling part essentially only by the pin bearing against a longitudinal end region of the slot. 
     
     
       7. Industrial truck according to  claim 6 , wherein the pin, in the clamping position of the clamping device, is located at an intermediate location between two longitudinal end regions of the slot. 
     
     
       8. Industrial truck according to  claim 1 , wherein the clamping device comprises a clamping position sensor which indicates that the clamping device is located in the clamping position. 
     
     
       9. Industrial truck according to  claim 7  wherein a clamping position sensor detects the location of the pin within the slot and the clamping position sensor recognizes from this that the pin is located at an intermediate location between the two longitudinal end regions of the slot. 
     
     
       10. Industrial truck according to  claim 9 , wherein the clamping position sensor is connected so as to move with the coupling part. 
     
     
       11. Industrial truck according to  claim 8 , further including a control/regulating device for controlling/regulating the movement of the drive arrangement, the control/regulating device stopping movement of the drive arrangement from the release position to the clamping position of the clamping device when the clamping position sensor indicates that the clamping device is in the clamping position. 
     
     
       12. Industrial truck according to  claim 1 , wherein the drive arrangement is connected to the clamping means for transmitting motive force via a toggle joint arrangement, the toggle joint arrangement having limbs that are each connected to one of the clamping means such that they can rotate, and having a toggle joint that is coupled to the drive arrangement. 
     
     
       13. Industrial truck according to  claim 6 , wherein the coupling part with the slot is located on a driven element of the drive arrangement and a toggle joint can be displaced along the slot. 
     
     
       14. Industrial truck according to  claim 1 , wherein the drive arrangement is an electrical drive arrangement. 
     
     
       15. Industrial truck according to  claim 1 , wherein the drive arrangement can be actuated by a control or operating unit of the industrial truck automatically or at the request of an operator. 
     
     
       16. Industrial truck according to  claim 9 , further including a control/regulating device for controlling/regulating the movement of the drive arrangement, the control/regulating device stopping movement of the drive arrangement from the release position to the clamping position of the clamping device when the clamping position sensor indicates that the clamping device is in the clamping position. 
     
     
       17. Industrial truck according to  claim 10 , further including a control/regulating device for controlling/regulating the movement of the drive arrangement, the control/regulating device stopping the movement of the drive arrangement from the release position to the clamping position of the clamping device when the clamping position sensor indicates the that the clamping device is in clamping position. 
     
     
       18. Industrial truck according to  claim 8 , wherein the drive arrangement includes a driven element having a coupling part with a slot, and a toggle joint displaced along the slot. 
     
     
       19. Industrial truck according to  claim 12 , wherein the drive arrangement includes a driven element having a coupling part with a slot, the toggle joint being displaced along the slot.